Field of the Invention
The present invention relates to an object information acquiring apparatus.
Description of the Related Art
A general ultrasound diagnostic apparatus transmits ultrasound waves using a probe that includes a plurality of acoustic detecting elements and receives echo signals reflected from the boundary between tissues inside an object to thereby obtain morphological information on the inside of the object. By doing so, it is possible to detect a disease segment such as a tumor. In recent years, in order to further improve the efficiency of detecting disease segments, imaging of physiological information (that is, functional information) of an object is gathering attention. As means for imaging the functional information, photoacoustic tomography (PAT) which uses pulsed lights and photoacoustic waves has been proposed.
Photoacoustic tomography is a technique of imaging an inner tissue serving as a source of photoacoustic waves using a photoacoustic effect that, when an object is irradiated with pulsed lights generated from a light source, the photoacoustic waves (typically ultrasound waves) are generated by absorption of the beams having propagated and diffused inside the object. In photoacoustic tomography, a change with time in the photoacoustic waves received by acoustic detecting elements is detected at a plurality of positions to obtain signals, and the obtained signals are analyzed mathematically. This analysis is also referred to as reconstruction processing by which information related to optical characteristic values inside the object can be visualized three-dimensionally.
Japanese Patent Application Laid-open No. 2012-179348 discloses an apparatus including a hemispherical probe in which a plurality of acoustic detecting elements that receive photoacoustic waves from an object are provided so that the light-receiving surfaces thereof are at different angles. The apparatus further includes a scanning mechanism that moves the hemispherical probe in the XYZ-directions in order to move a relative position of a high-resolution region determined by an arrangement of the object and the hemispherical probe.    Patent Literature 1: Japanese Patent Application Laid-open No. 2012-179348